Konig Eyepiece

[AndyH]

I forgot to mention............

I once owned a couple of (Gary) Russell Optics, Russell Optics & Machine , made Konig eyepieces in 2" size. If I remember correctly, a 19mm and 11mm(?).

Beautifully machined from lightweight Delrin(a joy to use in extremely low temps) and with ex military lenses. Well priced and gave very nice views.

He still makes lots of interesting and unusual eyepieces, but he sadly doesn't ship outside the U.S. I think some of his current crop, use Pentax sourced glass, which sounds enticing!

Andy.

[Alma]

I've never tried TAL's but they sound worthwhile, might see if I can find them. I alway felt University Optics sourced interesting eyepieces, but they've never seemed able to market them properly. The MK80 deserved a much bigger audience in my opinion but I don't think UO offer it any longer.

[AndyH]

U.O. offer nothing like what they used to in the past. A great, great shame.

Here's the link to the Japanese site. I once got a set of their 'volcano top' kellners, back when the £ to Yen was favourable.

Kokusai Kohki goods

Apologies if you already know about them.

The only place I've seen the MK80(and other ex U.O.) still for sale is here, at Kasai Trading Co.

ƒAƒCƒs[ƒX

Cheers,

Andy.

Edited October 9, 2011 by AndyH

[great_bear]

Just to clarify something stated on this thread.

You can only estimate the Apparent Field of View (aFOV) with maths, and in many cases the maths gives you an answer that's quite badly out (I had a long discussion on a Cloudy Nights thread a while back with David Knisely and Jon Issacs about this).

The best way to measure the Apparent Field of View of an eyepiece with any degree of accuracy, is to shine a torch through it backwards, projecting a big circle of light on the wall. Measure the diameter of the circle and the distance from the wall and... Well, I'm sure you can do the maths!

Edited October 9, 2011 by great_bear

[AndyH]

It's amazing how badly 'off' manufacturer quoted fields are, after you do a star timing.

I was gobbsmacked the first time I tried it.

Rather naughty.

Andy.

[John]

The funny thing is that it works both ways - there are eyepieces which are "infamous" for not delivering as much AFoV as claimed but also a few that actually deliver more.

The really confusing ones vary depending which production run you get - the old TAL 25mm plossl (which some reckon was actually a konig) was one of those - the actual apparent field of view varied between 50 and nearly 60 degrees with those.

[AndyH]

Agreed, John.

Tal seem to be notorious for vastly understating their quoted afov's.

The 24mm 2" UWA is quoted as 80 degrees. I reckon it's True fov is between 93-95 degrees !!

They quote their own plossls as 45 degrees. Again, nonsense. Whilst I don't have any apart for the newer 25mm plossl, they have to be in the 50 degree range(edit: from what I remember).

The Gen II plossl/Konigs are fun. Mine have all got different machined field stops in the Barrels.

Crazy.

Edited October 9, 2011 by AndyH

[DSTIEBS]

In the early Eighty's I compared the Meade 32mm 2" eyepiece (which i am buying again) to a University Optics 32mm 2" Konig eyepiece using a Meade 2120 LX3 and the Konig beat the Meade for sharpness and clearity but not buy much. If I could find a early UO 32mm konig I would buy it but I cannot find one. I did find the earlier Meade 32 SWA 2". I had to sell all my equipment in the early 90's and am just starting over again. I can't wait to set-up the Observatory. Clear-Sky's.

[Stargazer_00]

Is it "lets dig up an ancient post" day? This is from 2006

[SiriusB]

Is it "lets dig up an ancient post" day? This is from 2006

Lol.

Well in the interests of re~burying the post I've found you one

http://www.telescope...epiece_2__.html

Same eyepiece, different badge~honest!

Me, I love Konigs,

but in fairness there's undoubtedly better for your money out there these days.

[markse68]

On 09/10/2011 at 14:56, John said:

the old TAL 25mm plossl (which some reckon was actually a konig)

looks like a plossl 

https://skyviewer.de/selbstbau/TAL-ploessl/TAL-Ploessl.htm

Mark

 

[Louis D]

Hmmm.  The thread that would not rest in peace.  Put to rest initially in 2006, resurrected in 2011, 2013, and now 2023.  This might be something of a record for SGL.